Publications | EPEM Lab

Journal Publications

In preparation - ALD coating of SnO₂ and Al₂O₃
kappa-Ga₂O₃ for electronic devices (submitted)
Characterization of SnO₂ FET (accepted)
H. Y. Kang^[+], Y. Choi^[+], K. Pyeon, T. H. Lee, R. B. Chung^*, Experimental and theoretical investigation of the effect of Sn on κ-Ga₂O₃ growth, J Mater Sci 57, 19882–19891 (2022)
G. Lee^[+], M. Seong^[+], S. Kim^[+], K. Pyeon, and R. B. Chung^*, Conductive SnO_2-x thin films deposited by thermal ALD with H₂O reactant, Vacuum 200, 111018 (2022)
M. J. Yeom, J. Y. Yang, C. H. Lee, J. Heo, R. B. Chung^*, and G. Yoo^*, Low sub-threshold slope AlGaN/GaN MOS-HEMT with spike annealed HfO₂ gate dielectric, micromachines 12, 1441 (2021)
H. Y. Kang^[+], H. Kang^[+], E. Lee^[+], G. Lee, and R. B. Chung^*, Sn-induced phase stabilization and enhanced thermal stability of κ-Ga₂O₃ grown by mist-CVD, ACS Omega 6, 46, 31298 (2021)
Y. J. Jeong, J. Y. Yang, C. H. Lee, R. Park, G. Lee, R. B. Chung^*, and G. Yoo^*, Fluorine-based plasma treatment for hetero-epitaxial β-Ga₂O₃ MOSFETs, Appl. Surf. Sci. 558, 149936 (2021)
이경렬, 박류빈, R. B. Chung^*, 열처리 공정을 이용한 Si-doped β-Ga₂O₃ 박막의 전기적 특성의 이해, J. Microelectron. Packag. Soc., 27(4), 19-24 (2020)
R. B. Chung^*, Photo- and electro-luminescence studies of semipolar (112 2 ) In_xAl_1-xN, J. Appl. Physics 128, 043104 (2020)
D.-H. Hop, R. B. Chung, Y.-W. Heo, J.-J. Kim, and J.-H. Lee, Oxygen nonstoichiometry and electrical properties of La_2-xSr_xNiO_4+δ (0 ≤ x ≤ 0.5), J. Korean Ceram. Soc. 57, 416 (2020)
R. B. Chung^*, A. V. Sampath, and S. Nakamura, Strain relaxation process of undoped and Si-doped semipolar Al_xGa_1-xN grown on (20 2 1) bulk GaN substrate, J. Crystal Growth 533, 125467 (2020)

Domestic and International Patents and Applications

Domestic patent: 반도체 소자의 제조 방법 및 이에 의해 제조된 반도체 소자 (등록 번호: 10-2394975-00-00)
Domestic patent in preparation (2022)

Before 2019 (before joining KNU)

R. B. Chung^*, G. A. Garrett, R. W. Enck, A. V. Sampath, M. Wraback, and M. L. Reed, Optical polarization switching in low In-content InGaN MQWs on semipolar (20 21 ) GaN via strain engineering, Appl. Phys. Lett. 111, 231107 (2017)
R. B. Chung^*, L. E. Rodak, R. W. Enck, A. V. Sampath, M. Wraback, and M. L. Reed, Growth and impurity characterizations of AlN on (0001) sapphire grown by spatially pulsed MOCVD, Phys. Sol. Status A 213, 851 (2016)
R. B. Chung, D. Kim, S. K. Lim, J. S. Choi, K. J. Kim, B. H. Lee, K. S. Jung, H. J. Kim-Lee, W. J. Lee, K. Woo, B. Park, 4-Inch layer transferred GaN template by ion cut for nitride based light emitting diodes, Appl. Phys. Exp. 6, 111005 (2013)
R. Shivaraman, Y-R Wu, S. Choi, R. B. Chung, J. S. Speck, Atom probe tomography of III-Nitrides based semiconducting devices, Microscopy and Microanalysis 19, 956 (2013)
R. B. Chung^*, C. S. Han, C. C. Pan, N. Pfaff, J. S. Speck, S. P. DenBaars, and S. Nakamura, The reduction of the efficiency droop using AlInN/GaN superlattice electron blocking layer in light emitting diodes, Appl. Phys. Lett. 101, 131113 (2012)
* Highlighted in Semiconductor Today (link)
R. B. Chung, H. T. Chen, C. C. Pan, J. S. Ha, S. P. DenBaars, and S. Nakamura, The polarization field dependence of Ti/Al based ohmic contacts on N-type semipolar GaN, Appl. Phys. Lett. 100, 091104 (2012)
G. A. Garrett, P. Rotella, H. Shen, M. Wraback, D. A. Haeger, R. B. Chung, N. Pfaff, E. C. Young, S. P. DenBaars, J. S. Speck, D. A. Cohen, Carrier dynamics in active regions for ultraviolet optoelectronics grown on thick, relaxed AlGaN on semipolar bulk GaN, Phys. Stat. Sol. B 249, 507 (2012)
D. A. Haeger, E. Young, R. B. Chung, F. Wu, N. Pfaff, M. Tsai, K. Fujito, S. P. DenBaars, J. S. Speck, S. Nakamura, and D. A. Cohen, 384 nm laser diode grown on a (20 21 ) semipolar relaxed AlGaN buffer layer, Appl. Phys. Lett. 100, 161107 (2012)
R. B. Chung, O. Bierwagen, F. Wu, S. Keller, S. P. DenBaars, J. S. Speck, and S. Nakamura, Temperature dependent capacitance-voltage analysis of unintentionally doped Al_0.82In_0.18N grown on GaN, Jpn. J. Appl. Phys. 50, 101001 (2011)
R. B. Chung, F. Wu, R. Shivaraman, S. Keller, S. P. DenBaars, J. S. Speck, and S. Nakamura, Growth study and impurity characterization of Al_xIn_1-xN grown by metal organic chemical vapor deposition, J. Crystal Growth 324, 163 (2011)
Y. Zhao, S. Tanaka, Q. Yan, C. Y. Huang, R. B. Chung, C. C. Pan, K. Fujito, D. Feezell, C. G. Van de Walle, J. S. Speck, S. P. DenBaars, and S. Nakamura, High optical polarization ratio from semipolar (20 21 ) blue-green InGaN/GaN light emitting diodes, Appl. Phys. Lett. 99, 051109 (2011)
S. W. Kaun, M. H. Wong, S. Dasgupta, S. Choi, R. B. Chung, U. K. Mishra, and J. S. Speck, Effects of threading dislocation density on the gate leakage of AlGaN/GaN heterostructures for high electron mobility transistors, Appl. Phys. Express 4, 024101 (2011)
R. B. Chung, Y. Lin, I. Koslow, N. Pfaff, H. Ohta, J. S. Ha, S. P. DenBaars, and S. Nakamura, Electroluminescen characterization of (20 2 1) InGaN/GaN light emitting diodes with various wavelengths, Jpn. J. Appl. Phys. 49, 070203 (2010)
S. Yamamoto, Y. Zhao, C. C. Pan, R. B. Chung, K. Fujito, J. Sonoda, S. P. DenBaars, and S. Nakamura, High efficiency single quantum well green and yellow-green light emitting diodes on semipolar (20 2 1) substrates, Appl. Phys. Express 3, 122102 (2010)
I. Koslow, J. Sonoda, R. B. Chung, C. C. Pan, S. Brinkley, H. Ohta, S. Nakamura, and S. P. DenBaars, High power and high efficiency blue InGaN light emitting diodes on free standing semipolar (30 31 ) bulk GaN substrates, Jpn. J. Appl. Physics 49, 080203 (2010)
Z. Chen, Y. Pei, S. Newman, D. Brown, R. B. Chung, S. Keller, S. P. DenBaars, S. Nakamura, and U. K. Mishra, Growth of AlGaN/GaN/AlGaN double heterojunction field transistors and the observation of compositional pulling effect, Appl. Phys. Lett. 94, 171117 (2009)
Z. Chen, Y. Pei, S. Newman, R. Chu, D. Brown, R. B. Chung, S. Keller, S. P. DenBaars, S. Nakamura, and U. K. Mishra, Growth of AlGaN/GaN heterojunction field-effect transistors on insulating GaN using an AlGaN interlayer, Appl. Phys. Lett. 94, 112108 (2009)
K. Vampola, N. Fellows, H. Masui, S. Brinkley, M. Furukawa, R. B. Chung, H. Sato, J. Sonada, H. Hirasawa, M. Iza, S. P. DenBaars, and S. Nakamura, Highly efficient broad area blue and white light-emitting diodes grown on bulk GaN substrates, Phys. Stat. Sol. A. 206, 200 (2009)
Z. Chen, S. Newman, D. Brown, R. B. Chung, S. Keller, U. K. Mishra, S. P. DenBaars, and S. Nakamura, High-quality AlN grown on SiC by metal organic chemical vapor deposition, Appl. Phys. Lett. 93, 191906 (2008)
N. Fellows, H. Sato, Y. Lin, R. B. Chung, S. P. DenBaars, and S. Nakamura, Dichromatic color tuning with InGaN-based light-emitting diodes, App. Phys. Lett. 93, 121112 (2008)
H. Sato, R. B. Chung, H. Hirasawa, N. Fellows, H. Masui, F. Wu, M. Saito, K. Fujito, J. S. Speck, S. P. DenBaars, and S. Nakamura, Optical properties of yellow light-emitting diode grown on semipolar (11 2 2) bulk GaN substrates, Appl. Phys. Lett. 92, 221110 (2008)
H. Zhong, A. Tyagi, N. Fellows, F. Wu, R. B. Chung, M. Saito, K. Fujito, J. S. Speck, S. P. DenBaars, and S. Nakamura, High power and high efficiency blue light emitting diode on free-standing semipolar (10 11 ) bulk GaN substrates, Appl. Phys. Lett. 90, 233504 (2007)
H. Sato, A. Tyagi, H. Zhong, N. Fellow, R. B. Chung, M. Saito, K. Fujito, J. S. Speck, S. P. DenBaars, and S. Nakamura, High power and high efficiency green light emitting diode on free-standing semipolar (11 22 ) bulk GaN substrate, Phys. Stat. Sol. (RRL) 1, 162 (2007)
A. Tyagi, H. Zhong, R. B. Chung, D. F. Feezell, M. Saito, K. Fujito, J. S. Speck, S. P. DenBaars, and S. Nakamura, Semipolar (10 11 ) InGaN/GaN laser diodes on bulk GaN substrates, Jpn. J. Appl. Phys. 46, L444 (2007)
H. Zhong, A. Tyagi, N. Fellows, R. B. Chung, M. Saito, K. Fujito, J. S. Speck, S. P. DenBaars, and S. Nakamura, Demonstration of high power blue-green light emitting diode on semipolar (11 2 2) bulk GaN substrate, Electronics Lett. 43, No. 15 (2007)

Conference Proceedings

V. Parameshwaran, R. W. Enck, R. B. Chung, S. Kelley, A. V. Sampath, M. L. Reed, X. Xu, B. Clemens, Photoelectrochemistry of III-V epitaxial layers and nanowires for solar energy conversion, Proc. SPIE 10194, Micro- and Nanotechnology Sensors, Systems, and Applications IX, 101940N (2017)
R. W. Enck, A. V. Sampath, R. B. Chung, D. B. Knorr Jr., G. A. Garrett, M. L. Reed, Investigation of nucleation and intermixing at hetero-interface in III-Nitride - 4H-SiC structures, ECS Transactions 72, 9 (2016)
A. Bhargava, M. Scott, R. Taylor, R. B. Chung, K. Mrozek, J. Wolter, H. Z. Tan, Effect of cognitive load on tactile location identification in zero-g, Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems, 2005

Oral Presentations (International)

(Invited) R. B. Chung, R. E. Enck, and A. V. Sampath, Optical polarization switching in semipolar (20 2 1) InGaN QWs by strain engineering, Asia-Pacific Workshop on Fundamentals and Applications of Advanced Semiconductor Devices, July, 2019, Busan, S. Korea
R. B. Chung, L. E. Rodak, R. W. Enck, A. V. Sampath, M. Wraback, and M. L. Reed, Growth pressure dependence of crystal quality in (0001) AlN on sapphire grown by MOCVD under reduced pre-reaction condition, International Symposium on Compound Semiconductor, June 2015, Santa Barbara, CA, USA
R. B. Chung, E. C. Young, D. A. Haeger, F. Wu, M. Y. Tsai, S. Nakamura, S. P. DenBaars, J. S. Speck, and D. A. Cohen, Semipolar AlGaN on bulk GaN for UV-C diode lasers, Conference on Laser and Electro Optics, May 2011, Baltimore, MD, USA
R. B. Chung, O. Bierwagen, F. Wu, S. Keller, S. P. DenBaars, J. S. Speck, and S. Nakamura, Impurity incorporation and its effect on electrical property of Al_0.82In_0.18N grown on GaN by MOCVD, International Symposium on Compound Semiconductor, May 2010, Kagawa, Japan
R. B. Chung, Y. Lin, I. Koslow, N. Pfaff, H. Ohta, J. S. Ha, S. P. DenBaars, and S. Nakamura, Electroluminescence characterization of InGaN/GaN light-emitting diodes grown on semipolar (20 2 1) bulk GaN substrate, International Symposium on Compound Semiconductor, May 2010, Kagawa, Japan

Patents (US)

Patent# 8299452: Method for fabrication of semipolar (Al, In, Ga, B)N based light emitting diodes
Patent# 8357925: Optoelectronic device based on non-polar and semi-polar aluminum indium nitride and aluminum indium gallium nitride alloys

Footnotes

[+] authors with equal contributions